In evidence to the Science and Technology Committee in November 2020, Sir Patrick Vallance added that the intention of the circuit breaker was to enable the test and trace system—which in September had once again been found to be inadequate—to be more effective: The advice in September was about a circuit breaker with the intention of driving the numbers back to how they were in August, going back to the discussion on test and trace, because that means you have a greater chance of test and trace being effective. That takes more of the load in managing the disease and you may have to do fewer in terms of other non-pharmaceutical interventions. That is the logic behind that suggestion […].195 Professor Chris Whitty suggested that the case for a circuit breaker was not conclusive, reflecting “there is a lot of uncertainty in these things.”196